Signal system



June 1, 1965 F. s. CARAVELLA SIGNAL SYSTEM Original Filed Dec. 9, 1960 INVENTOR. FRAN K S. CARAVELLA ATTORNEY United States Patent 3,186,472 Sl'GNAL SYSTEM Frank S. Caravella, 43221 N. 13th St, Miiwauiree, Wis. Continuation of abandoned application Ser. No. 74,985, Dec. 9, 196d application Get. 22, 1%62, Ser. No. 233,187

8 Claims. (Ci. fits-422) This invention relates to a signal system, and more particularly to an arrangement for indicating an elevated temperature condition at the heating elements of a kitchen range.

This is a continuation from my application entitled Signal System and having Serial No. 74,985 now abandoned.

It is difiicult to determine the presence of a temperature elevation at the heating elements of a kitchen range unless at the time of observation the heating element is actuated in the case of a gas burner, or has been actuated for a sufiiciently long period in the case of an electric burner to produce a color change in the coil thereof. Since it takes a considerable period of time for a heating element and surrounding components to cool after the heating element has been deenergized, and since there is ordinarily no visual indication of the presence of a temperature rise in an electric heating element at low temperature settings, it would be desirable to equip kitchen ranges with an indicator arrangement to signal the presence of heat in excess of some predetermined temperature which would not burn a person coming in contact with the heating element.

It is, accordingl an object of this invention to provide an indicator arrangement that provides a signal that will indicate the presence of a dangerous temperature in a heating element after the heating element has been deenergized.

Another object of the invention is that of providing a signal system adapted for use in connection with the heating element of a kitchen range, which provides indicia of the presence of a temperature elevation in such heating element in excess of a predetermined temperature when the heating element is deenergized.

Still another object is in the provision of a signal system for use with either gas or electric ranges for indicating the presence of a temperature rise at one or more of the heating elements thereof, and which includes a normally deenergized visual indicator that is energized only by the presence of heat at the burner associated therewith in excess of some predetermined value.

A further object is to provide a system of the character described which includes a visual indicator such as an electric light, a temperature-responsive control located in heat exchange relation with the associated burner, and an electric circuit which includes the control and indicator and is adapted to be connected to a power sourcethe control being normally open to interrupt the circuit, but being closed by a temperature elevation of predetermined quantity so as to close the circuit and effect energization of the indicator, regardless of whether said power source is energized.

Additional objects and advantages of the invention will become apparent in the course of the following description.

Embodiments of the invention are illustrated inthe accompanying drawing, in which "ice FIGURE 1 is a broken longitudinal sectional view through a top burner of an electric range which embodies the invention;

FIGURE 2 is a bottom plan view of the heating element shown in FIGURE 1, with the control element of the signal system attached thereto;

FEGURE 3 is a broken longitudinal sectional view through a top burner of a gas range which embodies the invention;

FIGURE 4 is a broken top plan view of the grating and drip pan shown in FIGURE 3;

FIGURE 5 is a sectional View taken along the length of the control of the signalling arrangement;

FIGURE 6 is a transverse sectional view taken generally along the line 6-6 of FIGURE 2; and

FIGURE 7 is a broken transverse sectional view taken generally along the line 7-7 of FIGURE 3.

The exemplary structural embodiment of the signalling arrangement shown in the drawing, and referring first to FIGURES 1, 2, and 6, is used in conjunction with a conventional electric range, which has a countertop or top wall It) that is usually generally planar and horizontally disposed, and is provided with one or more openings therethrough each of which may have a peripheral edge portion thereof equipped with a support ring 11. Usually, a drip pan of generally concave configuration is disposed below the opening in the top wall 10 and may be secured to the top wall by any suitable means, such as the cap screws 13. In the form shown, the drip pan 12 is provided centrally with an opening or aperture 14 therethrough.

Mounted Within the opening in the top wall 10 of the range is a heating element of conventional form, which in FIGURES 1, 2 and 6 is an electric heating element having a plurality of coils respectively denoted with the numerals 15, i5, 15", each of which is of generally circular configuration and is provided with the usual electric resistance Wire suitably insulated therefrom as by means of a heat-resistant ceramic material. The heating coils are of progressively diminishing diameter and are concentrically located, and are rigidly interconnected at their ends as shown at 16 either integrally or by means of a common support structure rigidly secured thereto. The common mounting of the coils is secured to one side of a hinge 17, which has the other side thereof secured to a mounting member 18 that is rigid relative to the range and may be riveted or otherwise anchored to the top wall It) thereof. Thus, the heating element, and in particular the coils thereof, may be pivoted upwardly in a counterclockwise direction as viewed in FIGURE 1 to facilitate cleaning of the element and to provide ,may be wholly conventional.

A temperature-responsive control 19 is located in heat exchange relation with the heating element, and may be secured thereto as shown'at 20 by any convenient means as, for example, spot welding, brackets, by a thermosetting adhesive (one of the epoxy resins), etc. The

control 19 is an on-oif switch which is normally in its off condition so as to interrupt the electric circuit connected thereto, but which is shifted to an on condition by the application of heat thereto in excess of a predetermined temperature. Thus, the temperature-responsive control or switch 19 may be completely conventional, and there- 'fore may be any of the bimetal switches commercially available. For purposes of illustration, a typical switch is shown in FIGURE 5, and includes an outer casing 21 having end walls 22 and 22 formed of insulating material. The casing defines a compartment 23 therewithin, and extending thereacross in rigid attachment to the end walls 22 and 22' is a conductor 24 having a heat-responsive eonductor element 25 electrically attached thereto, as by means of rivets 26. Also extending between the end walls in rigid attachment thereto is a conductor 27 adapted to be electrically engaged by the conductor element 25. The conductors 24 and 27 are respectively equipped with terminals 28 and 29 that are connected to the wires of an electric conduit 36 having a pair of conductors 31 and 32 adapted to be connected to a source of power such as l10-volt alternating current.

The conduit Till is connected to an indicator 33 that is preferably a visual indicator in the form of an electrically actuated light. The light, and more particularly the socket therefor, is fixedly secured to the bracket structure 34 which may be supported by the drip pan 12 by a fastener 35 that secures the bracket structure thereto. Ordinarily, the light 33 will be protected by a transparent cover 36 which may be glass, and will be removably secured to the bracket structure so as to provide access to the light 33 for changing the same. It will be apparent from FIG- URE 1 that the light 33 is located so that it will be visible through the opening 14 in the drip P211112.

The circuit defined by the conductors 31 and 32, the control l9 and light 33 will be arranged so that the cnductor S2 is connected directly to one side of the light 3-3 and the conductor 31 is connected to the opposite side of the light through the control 1% (the terminals 23 and 29 thereof), which is then in series with the conductor Ordinarily, the control 19 is open and therefore the con ductor element 25 will be withdrawn from engagement with the conductor 2'7, and as a result the light 33 will be deenergized and no current will flow through the circuit. However, when the control 19 is subjected to a temperature in excess of a predetermined value, the heat-responsive element 25 will elongate upwardly and into engagement wit-h the conductor 27, as shown in FIGURE 5, at which time a circuit will be defined between the conductors 24- and 27 and the light 33 will be energized. This condition will prevail until the conductor element 25 cools to a temperature below such predetermined value. Usually, the value to which the control 19 is set will be one which is not uncomfortable to the touch and which will not cause burning it the heating element is touched.

In FIGURES 3, 4 and 7, the signal device is shown in association with a gas range having a countertop or top wall Illa provided with an opening therein, the perimetric edges of which are defined by a depending wall portion 37 having an inwardly turned flange at its lower end which supports a drip pan 12a thereon which extends under the opening and is provided centrally with a large opening 14a therethrough. A gas burning heating element 3%; is disposed within the openin in the range top and is located above the drip pan 12a. The heating element 38 i supplied with fuel through a pipe or conduit 39, and the heating element and conduit assembly may be supported in any conventional manner which usually will permit removal therefor for cleaning purposes. A grating 40 is disposed above the drip pan 32a, and is adapted to support cooking vessels in heat exchange relation with the heating element 38.

The signal system is substantially the same as that heretofore described, except that the light 33 and its socket is supported by a bracket iii Welded or otherwise secured to the drip pan 12a along one side thereof, and the drip pan thereat is provided with an opening 42 therethrough, which if desired may have a transparent shield 43 extending thereacross to protect the light 33. The control for the signal system is identical to that heretofore described except for the manner in which it is mounted. Thus, the device has fixedly secured thereto a generally U- shaped bracket having a pair of spaced apart spring legs 44% and 4-4 which extend upwardly through an opening provided therefor in the drip pan lilo. The spring legs are adapted to respectively engage with a frictional grip a pair of arcuately spaced struts it? and -3-7 of the grating it? and which are radially disposed. Thus, the control 19a is removably secured to the grating 25), and is located in heat exchange relation with the heatin ele rent 38, and the function of the signal device is precisely the same as that heretofore described.

It will therefore be seen that the invention provides an indicator arrangement that signals a dangerous temperature in a heating element even after the heating element is deenergized. Accordingly when my invention is used in conjunction with an electric stove, it signals a dangerous condition when the current is no longer flowing through the heating element of the stove.

While in the foregoing specification embodiments of the invetnion have been set forth in considerable detail for purposes of making an adequate disclosure thereof, it will be apparent to those skilled in the art that numerous changes may be made in such details without departing from the spirit and principles of the invention.

I claim:

1. In combination; a kitchen range having a generally horizontal top wall provided with a heating element therein for heating a vessel disposed thereabove, an independent electrically actuated indicator means for indicating the presence of a temperature in said element in excess of a predetermined value after said heating element is no longer energized, a temperature-responsive control means mounted in heat exchange relation with said element, and an electric circuit including said indicator means and control means and being adapted to be connected to an independent power source, said circuit being operable regardless of whether said heating element is energized, and said control means functioning solely to energize and deenergize said indicator means, said control means being normally open to maintain said indicator in a deenergized state when said heating element is below a predetermined temperature for which a person would be burned by contact therewith and being closed by elevation of the temperature of said element above such predetermined value to complete said circuit and thereby effect energization of said indicator regardless of whether said heating element is energized.

2. The combination of claim 1 in which said indicator is an electric light to provide a visual indicia of the temperature of said element.

3. The combination of claim It in which said control means is a bimetallic thermo-responsive switch.

In combination, a kitchen range having a generally horizontal top Wall provided with an opening therein, a drip pan carried by said range below said opening, an electric heating element located in said opening and above said drip pan for heating a vessel disposed above said kitchen range, a temperature-responsive control means mounted in heat exchange relation with said element, a visual indicator means for indicating the presence of a temperature in said element in excess or a predetermined value regardless of whether said electrical heating element has current flowing therethrough and an electric circuit including said indicator means and control means, said control means being a separate unit and being adapted to be connected to circuit that is independent of said heating element, said control mean functioning solely to energize and deenergize said indicator means, said control means being normally open to maintain said indicator in a deenergized state when said heating element is below a predetermined temperature for which a person could be burned by contact therewith and being closed by elevation of the temperature of said element above such predetermined value to complete said circuit and thereby effect energization of said indicator means.

5. The combination of claim 4 in which said control is a bimetallic thermo-responsive switch.

6. The combination of claim 4 in which said control means is mounted intennediate said heating element and drip pan, and in which said indicator means is mounted below said drip pan, said drip pan having an opening therein through which said indicator means is visible from above said top wall.

7. The combination of claim 4 in which said heating element is electrically actuated.

8. The combination of claim 4 in which said heating element is a gas burner.

References Cited by the Examiner UNITED STATES PATENTS Rollins 116-1145 Brown et a1 116-1145 Johnson 2 1925 Clark 219515 Kitson 340-252 Mayer 158122 Kinsella 340-252 Moiyneaux et a1 236-20 X JAMES W. WESTHAVER, Primary Examiner.

FREDERICK L. MATTESON, JR., Examiner. 

1. IN COMBINATION: A KITCHEN RANGE HAVING A GENERALLY HORIZONTAL TOP WALL PROVIDED WITH A HEATING ELEMENT THEREIN FOR HEATING A VESSEL DISPOSED THEREABOVE, AN INDEPENDENT ELECTRICALLY ACTUATED INDICATOR MEANS FOR INDICATING THE PRESENCE OF A TEMPERATURE IN SAID ELEMENT IN EXCESS OF A PREDETERMINED VALUE AFTER SAID HEATING ELEMENT IS NO LONGER ENERGIZED, A TEMPERATURE-RESPONSIVE CONTROL MEANS MOUNTED IN HEAT EXCHANGER RELATION WITH SAID ELEMENT, AND AN ELECTRIC CIRCUIT INCLUDING SAID INDICATOR MEANS AND CONTROL MEANS AND BEING ADAPTED TO BE CONNECTED TO AN INDEPENDENT POWER SOURCE, SAID CIRCUIT BEING OPERABLE REGARDLESS OF WHETHER SAID HEATING ELEMENT IS ENERGIZED, AND SAID CONTROL MEANS FUNCTIONING SOLELY TO ENERGIZE AND DEENERGIZE SAID INDICATOR MEANS, SAID CONTROL 